Grandmaster-level chess without search

OT: what's the state of the art in non-GM level computer chess?

Say I want to play chess with an opponent that is at about the same skill level as me, or perhaps I want to play with an opponent about 100 rating points above me for training.

Most engines let you dumb them down by cutting search depth, but that usually doesn't work well. Sure, you end up beating them about half the time if you cut the search down enough but it generally feels like they were still outplaying you for much of the game and you won because they made one or two blunders.

What I want is a computer opponent that plays at a level of my choosing but plays a game that feels like that of a typical human player of that level.

Are there such engines?

Maia does this reasonably well! You can play against it on Lichess. I have gotten a few "feels like a human" moments when playing against it - for example, getting it to fall into a trap that could trick a human but would easily be seen by a traditional search algorithm. It's not adjustable but there are a few different versions with different ratings (although it's not a very wide range).

https://www.maiachess.com/

https://lichess.org/@/maia1

Piggy-backing off this - does anyone know of a quick way to evaluate the maia weights from python or js for a single board state? I'm trying to hack something together with my own search func intended for human play and I can't quite figure it out from the cpp in Lc0.

A bit late, but I wrote up an example inference script here: https://gist.github.com/mcognetta/7a98e50859664b8efbb4ec094a...

It is a bit roundabout, since it involves converting maia models to onnx before loading into pytorch and some outdated versions of libraries (maia/lc0 are a little old). We were using this for transfer learning for a competition, so we needed some flexibility that we didn't know how to do quickly/easily in TF.

Hope this helps.

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Personal note: given your interest in chess ai and your starcraft username, I think we would have a lot of shared interests. Feel free to reach out (info is in my profile).